Request for reviews: 7188176: The JVM should differentiate between T and M series and adjust GC ergonomics

[Tao Mao]

As commented in the code

!     // for now, use same gc thread calculation for M-series as for niagara-plus
!     // in future, we may want to tweak parameters for nof_parallel_worker_thread

after discussion with Vladimir and Jon, we should treat them separately 
b/c they are QUITE different types and will tune gc threads differently 
for the two machines in future.

But, yes, they are using same parameters for now since we are awaiting 
performance feedback from customers or performance team.

Thanks.
Tao

On 9/21/2012 3:32 PM, Vitaly Davidovich wrote:
>
> Hi Tao,
>
> Why not combine M series and niagara_plus into the same if block (i.e. 
> if (niagara_plus || m_series)) since they use same parameters for 
> calculating the parallel workers number?
>
> Thanks
>
> Sent from my phone
>
> On Sep 21, 2012 6:22 PM, "Tao Mao" <tao.mao at oracle.com 
> <mailto:tao.mao at oracle.com>> wrote:
>
>     7188176: The JVM should differentiate between T and M series and
>     adjust GC ergonomics
>
>     webrev:
>     http://cr.openjdk.java.net/~twisti/7188176/
>     <http://cr.openjdk.java.net/%7Etwisti/7188176/>
>     <http://cr.openjdk.java.net/%7Etwisti/7188176/>
>
>     The code has been tested on real M-series machine. In the testing,
>     it was able to recognize the M-series machine and do the correct
>     calculation of GCThreads.
>
>     Thanks.
>     Tao Mao
>